What I learned from AirGas today
IF you bring in your own dewer, the charge works out to 5/6 USD per liter because they first have to chill down the unit and that wastes product ... umm sure..
HOWEVER... you can RENT a 180 LITER DEWER for about $2 per day (60/mo) and then the LN2 only costs you $1 buck a liter. Since they weigh 5 or 600 pounds, they need to be delivered ($27 approx in my case) but they won't go up or down stairs. This would work for me since I have a gated back yard with a sidewalk that runs just next to my current office, and, my fuure basement laboratory..
All I'd need to do is drill a hole into the house and run an insulated tube down (the wife already has rejected any thoughts of LN2 in the office) to the basement and I'm set
Seems like the best solution
If 180 liters lasted me two months the cost would be about $240, or, $4 per day
Ohhh, can't wait for my daughter to move out lol